US2449318A - Electrostatic ironing apparatus - Google Patents

Description

Sepvt.' 14. 1948- E; c. PITMAN ETAL. 2,449,318

ELECTRQSTATIC IRONING APPARATUS Filed April 18, 1944 fzven'or Eaae C. Pa

Erl/wzl. @ra/2M by @wwf A521029@ Patented Sept. 14, ,1948

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Crandell, "WllesleyjMass assignors4 toConpo *f Shoe Machinery"Corporation, Boston,fMa`s's.,fa

corporation =off Delaware Application April 18, 1944,- `Serial No. 5312532" 4 Claims.

1 This invention relates to'electrostatic heating apparatus and relates more particularly to'hand irons providing electrostatic heat for pressing and a dampoloth, the cloth is a dielectric in the electro'static fields and byhysteiesisfaction, is heated. The power absorbed'byrthe clothl from the electrostatic fields and` therefore, the heat produced in' the elothl` is :proportional-tothe moisture content of the cloth. Therefore since the heatv produced varies in accordance with the dampness of the cloth, as the cloth is dried by the application of the iron, the heat-becomes less and less until when the cloth is completely dry, relatively no heat is produced.

The ironing surface of the iron is not heated so that it may be left upon the surface of the cloth being ironed, for any period of time with= out any scorching or burning of the cloth.

The iron is designed for use with vanironing board or table preferably having a metallic ply formed in its supporting surface. This metallic ply forms a free electrode which is capacity coupled. to the electrodes in the iron, when the iron is placed upon the table, the electrical capacity between the free electrode and the electrodes in the iron being greater than the capacity between the alternately connected electrodes in the iron. The effective electrostatic field is, therefore, provided to a major extent between the free electrode and the other electrodes. By providing such a free electrode, the size of the hand iron may be reduced considerably over that which would be necessary were the free electrode not provided, and lower voltages may be supplied to the electrically connected electrodes.

The free electrode since not being connected in the electrical circuit, may be grounded so that no electrical charges may be induced upon its surface.

An object of the invention is to provide electrostatic heat with a hand iron.

Another object of the invention is to utilize a metallic cloth supporting surface as a free electrede and to utilize electrodes in a hand iron 2f. connected `to a 'high 'frequency' 'oscillatory' for" heating. the `cloth with Velectrostatic heat.-

The invention will'now be described with refer-ff encetothe drawing; of which:

Figli isa projected view of" an ironing table" having; va high frequency `oscillator 'contained-e therein, and of a hand-ironhavin'g electrodesffin its base connected to the oscillator; the table'liaw'` ing 'a metal ply; andv Figyz is a sectional `View alonglthe linesff2-`2cfi Fieri.

The table 4illustrate'ci'by Figgl hasthe -doors Ill which yprovide access tofthel oscillator'l I supporte f edI inthe .interior ofA the table.-'llie oscillator I I* `lis`"a conventional'- oscillator-utilizing electronic.y

tubes-ior lproducing high frequency alternating i currentv which, for example;4 may be'twenty meg-atil cycles" The table top I-'2=' has *a metallic ply f I3-1which 'in f; ironing-'acts'v as a freeelectrode asn will bei` de:A scribed.

The hand iron Ill has in its base, the metallic electrodes I5, which are connected to each other and to one side of the oscillator II, and the metallic electrodes I6 which are connected to each other and the other side of the oscillator. The electrodes I5 and I6 are parallel and extend crosswise the iron with their lower surfaces parallel to the lower surface of the iron. The electrodes I5 are arranged alternately with the electrodes I6 so that they may be considered as interlaced.

The body and handle of the iron should be of non-metallic material for avoiding the production of electrostatic charges thereon,

When a damp cloth is placed on the table top I2 and the oscillator I I is energized and the iron I4 pressed against the cloth, electrostatic elds are produced between the electrodes I5 and I6 and the metallic ply I3 below the surface I2 acting as a free electrode capacitively coupled to the electrodes I5 and I6. The electrostatic fields produce heat in the cloth so that the cloth may be ironed by movement of the hand iron I4 in the usual manner.

It is preferred that the oscillator Il be of the push-pull type disclosed in the E. L, Crandell, U. S. Patent No. 2,298,038. With this type of oscillator, a free electrode is maintained at ground potential so that there can be no voltages induced in the table top I2 and no harm caused by electrical shock, to the operator of the iron.

While one embodiment of the invention has been described for the purpose of illustration, it should be understood that the invention is not limited to the exact apparatus and arrangement of apparatus disclosed as modifications thereof may be suggested by those skilled in the art without departure from the essence of the invention.

What is claimed is:

1. Ironing apparatus comprising in combination, a hand ironer having a body portion of non-metallic material, a plurality of spaced electrodes embedded within the body portion of said ironer, an oscillator, means connecting said electrodes to Said oscillator, a cabinet housing said oscillator, and means forming a portion of said cabinet providing a surface for supporting the material to be ironed and providing a free electrode capacitively coupled to said electrodes when said ironer is placed upon said material.

2. Ironing apparatus comprising in combination, a hand ironer having a body portion of nonmetallic material, a plurality of interlaced, spaced electrodes embedded within the body portion of said ironer, a pair of electrical conductors connecting alternate of said electrodes together, an oscillator, means connecting said conductors to said oscillator, a cabinet housing said oscillator, and means forming a portion of said cabinet providing a surface for supporting the material to be ironed and providing a free electrode capacitively coupled to said electrodes when said ironer is placed upon said material.

3. Ironing apparatus comprising in combination, a hand ironer having a body portion of non-metallic material, a plurality of interlaced spaced electrodes embedded within the body portion of said ironer, a pair of electrical conductors connecting alternate of said electrodes together, an oscillator, means connecting said conductors to the output circuit of said oscillator, a cabinet housing said oscillator, said cabinet providing a surface for supporting the material to be ironed, and means located below said supporting surface providing a free electrode capacitively coupled to said electrodes when said ironer is placed upon said material.

4. Ironing apparatus comprising, an oscillator,

a housing for said oscillator, a slab-like support providing an ironing surface, said housing being disposed immediately below and attached to the under side of said support, a hand ironer having a body portion of non-metallic material, a plurality of spaced electrodes embedded Within the body portion of said ironer, means connecting alternates of said electrodes to opposite sides of the output circuit of said oscillator, and means located below the ironing surface of said slab-like support and providing a free electrode capacitively coupled to said electrodes when said ironer is brought into ironing Contact with material placed upon said support.

EARLE C. PITMAN.

ERVIN L. CRANDELL.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS Number Name Date 1,484,879 Fogwell et al Feb. 26, 1924 2,133,494 Waters Oct. 18, 1938 2,137,189 Whitman Nov. 15, 1938 2,298,038 Crandell I Oct. 6, 1942 2,332,468 Lofgren Oct. 19, 1943 2,342,846 Crandell II Feb. 29, 1944 FOREIGN PATENTS Number Country Date 518,691 Great Britain Mar, 5, 1940 OTHER REFERENCES Taylor, John PI., Electronics magazine, November 1943, pages 10G-7.

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